Screen Media Use and Mental Health of Children and Adolescents

Key Points Question Does reducing leisure-time screen media use improve mental health among children and adolescents? Findings In this prespecified secondary analysis of a randomized clinical trial including 89 families (181 children and adolescents), reducing screen media use had an overall positive effect on children’s and adolescents’ behavioral difficulties. The most noticeable benefits associated with reduced screen media use was a decrease in internalizing behavioral issues and enhanced positive social interactions. Meaning The findings provide evidence for a causal link between a short-term reduction in screen media use during leisure and improvements in children’s and adolescents’ psychological symptoms.


eAppendix.
Estimating the expected impact of reducing screen media use on the distribution of SDQ (Strengths and Difficulties Questionnaire) total difficulties score classifications in normal, borderline, and abnormal ranges in Danish normative data in 10-12-year-old children The clinical relevance of the effect size (mean difference in change of -1.67 points in the total group and -2.52 in boys and -0.92 in girls between intervention and control) with respect to population impact can be quantitatively gauged by comparing intervention effects against normative data shifts in a defined population.We analyzed the expected impact of reducing screen media use on the SDQ total difficulties score among Danish children aged 10-12 years using normative Danish data, should a similar intervention be widely implemented.We simulated the expected distributional shifts in the SDQ total difficulties score resulting from the mean reductions.The norm data mean SDQ total difficulty scores are 6.02 points (SD 5.24) for boys and 5.27 points (SD 4.72) for girls.Distribution and cut-off scores in the norm data delineating normal, borderline, and abnormal score ranges are: Boys: Normal: 0-10 points, accounting for 83.1% of the population.Borderline: 11-13 points, accounting for 7.1% of the population.Abnormal: 14-40 points, accounting for 9.8% of the population.
Normative SDQ Data from Denmark were obtained from URL: https://www.sdqinfo.org/norms/DanishNorms.html (accessed April 23 2024)) with the material described in Niclasen J, Teasdale TW, Andersen A-MN, et al.Psychometric properties of the Danish strength and difficulties questionnaire: the SDQ assessed for more than 70,000 raters in four different cohorts.PLoS ONE.2012;7(2):e32025.

Adjustment of mean scores and estimated distributional change:
For boys: Mean after = 6.02 -2.52 = 3.50 points For girls: Mean after = 5.27 -0.92 = 4.35 points Using z-scores and the standard normal distribution's cumulative density function (CDF), we recalculated the expected proportions within each SDQ category post-intervention.These calculations were derived from the following z-score transformation:

𝑧 = (𝑋 − 𝑀𝑒𝑎𝑛) 𝑆𝐷
Where  is the cut-off score for the respective SDQ total difficulties range scores, Mean is the adjusted mean postintervention, and SD is the standard deviation (assumed to the unaffected).
And the cumulative proportion calculations: Where Φ denotes the CDF of the standard normal distribution,  ( ≤ ) represents the probability that the total difficulties score  for a randomly selected child does not exceed the cut-off value , where  corresponds to the upper limit of a specified SDQ category (e.g., 10 for the 'Normal' range in boys, and 8 for the Normal' range in girls), and  is the z-score calculated using the adjusted mean and standard deviation for that cut-off value.

The expected impact of reducing screen media use on the SDQ total difficulties score
This simulated analysis suggests that widespread application of similar interventions could result in a meaningful change in the proportions of children rated as 'abnormal' and 'borderline'.
For the Normal category cut-off (0-10 for boys, 0-8 for girls) we found the new proportions after the intervention to be approximately 89.3% for boys and 78.0% for girls.
For the Borderline category (11-13 for boys, 9-11 for girls), the proportions were estimated at 7.2% for boys and 14.0% for girls.
For the Abnormal category (14-40), we estimated 3.5% for boys and 8.0% for girls.

Mean difference in change represents the estimated
Comparison of Total Difficulties Scores at Baseline Median and quartiles are compared for participants with complete data at baseline and follow-up and for participants with missing data at follow-up.*Although 19 participants had missing data at follow-up only 12 of these participants had complete baseline data for the total difficulties score.Baseline columns present raw mean and standard deviations.Change columns present estimated within-group mean change scores and 95% confidence intervals predicted from the regression models.Mean difference in change represents the estimated intervention effect (interaction between group allocation and time adjusted for age) predicted from the mixed tobit regression models.Comparison of Norm Data Proportions to Simulated Proportions The table present the proportions in each diagnostic category from the Danish norm data, and the estimated proportions in each diagnostic category after simulation of a widespread application of the screen media use reduction intervention.For more information see the supplemental text on the next page.
eFigure.Flow Chart eFigure 1: Flow of participants from invitation to analysis © 2024 Schmidt-Persson J et al.JAMA Network Open.eTable 1. eTable 2. Analyses for Behavioral Strengths and Difficulties intervention effect (interaction between group allocation and time adjusted for age) predicted from the mixed tobit regression models.eTable 2. Analyses for Behavioral Strengths and Difficulties (continued) eTable 3.